Fine-needle aspiration cytology of bronchocentric granulomatosis: a potential diagnostic pitfall.

Bronchocentric granulomatosis (BCTG) is a rare disease associated with bronchial asthma and bronchopulmonary aspergillosis. Idiopathic forms are rarely encountered. We report on a case of BCTG showing clinical, radiological, and cytological evidence suggestive of adenocarcinoma of the lung. The patient is a 69-yr-old female, lifetime nonsmoker with multiple sclerosis who was admitted with a history of ascending cholangitis. Admission chest X-ray documented a 1.5-cm nodule in the left upper lobe of the lung. This was confirmed by CT scan. The lesion was slowly growing. Bronchoscopic examination was normal. Bronchial brushings were inconclusive. A transthoracic fine-needle aspiration showed sheets of highly atypical epithelium with occasional small dyshesive clusters. There was an inflammatory background that was believed to represent tumor diathesis. The cytological interpretation was "suspicious for adenocarcinoma." The patient underwent left upper lobectomy. The lung showed multiple peribronchial granulomas with intense peribronchial lymphoid infiltrate extending into the bronchial mucosa, causing cytological atypia and focal ulceration. Special stains for microorganisms were negative. The patient recovered from surgery and shows no signs of infection. We conclude that BCTG and related lesions can give cytological features that are suggestive of malignancy. Cytological material obtained from these lesions should be interpreted with caution.